Thermoplastic film, and in particular polyolefin materials, have been used for some time in connection with packaging of various articles including food products which require protection from the environment, an attractive appearance, and resistance to abuse during the storage and distribution cycle. Coextruded multilayer thermoplastic packaging has been used conventionally for a considerable number of years in food packaging, and especially in the packaging of cheese and processed cheese. For example, cheese manufacturers have utilized multilayer thermoplastic films to package processed cheese utilizing a “hot pack” method. In the hot pack packaging process, an extrusion nozzle discharges molten cheese into a packaging film tube. The film tube moves away from the nozzle at a steady rate to allow the film tube to fill with the cheese product. Sizing rolls flatten the longitudinally sealed film tube and the molten cheese product to a desired product thickness. To solidify the cheese, the cheese-filled film tube moves over cooling wheels or through a cold water bath that cools the cheese. To produce individual cheese slices, the cooled cheese tube is transversely cut and sealed. To produce a loaf-type cheese product, packaging material is first inserted into a forming mold to form a pouch and then passed to a filling station where hot melted cheese is poured into the pouch. As the cheese cools, it generally takes the form of the pouch inside the forming mold. A fin seal or lap seal closure is used for sealing of the pouch, to provide a packaged cheese product.
Because the packaging film surface that contacts the cheese is typically smooth, the cheese surface develops a glossy appearance which is generally perceived by consumers as having an undesirable “processed” look. To overcome this deficiency, cheese manufacturers have embossed the packaging film just prior to the packaging process. Embossing of the packaging film requires heating the film to its softening temperature and contacting the film onto an embossed surface, typically an embossing nip roller which produces an inverse three-dimensional replication of the embossed surface on the film. As the liquid cheese is pumped into the product cavity, it fills the depressions of the embossed surface of the film leaving a dull finish on the surface of the cheese product when the film is removed. However, as new high speed hot packaging equipment and processes come into use, it has become more difficult to obtain a desirable cheese appearance with conventional embossed packaging films and methods.
Therefore, there is the need for improved packaging films and methods.